No Esteem for Man
"Stop trusting in mere humans, who have but a breath in their nostrils. Why hold them in esteem??"
One day the Lord’s reign will be realized from His holy mountain in Jerusalem. But until that time comes, get right! (Paraphrasing Isaiah’s writings)
So Judah was in a bad situation. They had gotten themselves in a pinch. They left their brothers and turned their backs on God. This was done all on account of following the customs of foreigners. They were regarding man. They made pledges, consulted fortune tellers and worshipped idols.
So Isaiah announced that there is coming a time when the Lord will set this straight. The people of Judah were going to need to hide in the rocks. God would bring everything low. No more worrying about stuff. It would be terrifying.
Stop esteeming humans. They are nothing compared to God.